1. Field of the Invention
This invention relates in general to medical equipment, and in particular to ventilation tubes, such as endotracheal and tracheostomy tubes.
2. Description of the Prior Art
Whenever hospital patients require mechanical ventilation, a ventilation tube delivers air or oxygen to the patient from a remote source. The end of the ventilation tube is either inserted into the patient's nostril, or an incision is made so that the tube may be inserted directly into the patient's trachea. If the patient moves, the tube may drag against sensitive tissue inside the patient's nostril or trachea, causing pain and injury.
One experimental ventilation tube, which somewhat alleviated this condition, had an angled central member inserted between the end of the ventilation tube and the air or oxygen source, near the patient. The angled central member was brass and had a threaded connection on each end. The angle in the central member eased the pressure some, but still did not allow the patient to move very much.
Swivel couplings are used in some types of medical equipment to allow rotational movement. For example, U.S. Pat. Nos. 4,416,273 and 4,240,417 show couplings for an endotracheal tube having swivel connectors on each end. In each of these patents the swivel coupling allows only rotational movement, with no axial translation.